C/Visual C - AYUDA con el STL de SGI

#include <iostream>
#include <string>
#include <hash_map.h>

class Equal
{
public:
size_t operator()(string const &s1, string const &s2) const
{
return (s1 == s2);
}
};

class hashString
{
public:
size_t operator()(string const &str) const
{
hash<char const *>
h;

return (h(str.c_str()));
}
};

int main()
{
hash_map
<
string,
int,
hashString,
Equal
>
months;

months["january"] = 31;
months["february"] = 28;
months["march"] = 31;
months["april"] = 30;
months["may"] = 31;
months["june"] = 30;
months["july"] = 31;
months["august"] = 31;
months["september"] = 30;
months["october"] = 31;
months["november"] = 30;
months["december"] = 31;

cout << "february -> " << months["february"] << endl <<
"april -> " << months["april"] << endl <<
"june -> " << months["june"] << endl <<
"november -> " << months["november"] << endl <